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Pd-catalyzed aminocarbonylation in the presence of Xantphos as a ligand was used to transform lactam-, lactone-, and thiolactone-derived triflates into N-methoxy-N-methyl or morpholine Weinreb amides. The method could also be applied to synthesize dienones in which one of the double bonds is embedded in a heterocyclic moiety, as useful substrates for Nazarov cyclization.

The development of an enantioselective and diastereocontrolled approach to 8a-epi-D-swainsonine from achiral furtural is described. The reaction demonstrates the use of Noyori reduction, palladium-catalyzed glycosylation, diastereoselective dihydroxylation, and one-pot reductive cyclization.

Xantphos is an efficient ligand for palladium-catalyzed allyl cross-coupling reactions of aryl bromides and triflates with allylindium reagents generated in situ from allyl acetates and indium. These reactions have occurred in high yield with good functional group tolerance and this method has complemented the existing synthetic methods.

A convenient method is developed for synthesizing 2-bromo-3-aroyl-benzo[b]furans from readily accessible precursors. The 2-bromo group is used as a versatile synthetic handle in both palladium-mediated couplings and direct nucleophilic substitutions to provide access to a wide range of 2-substituted-3-aroyl-benzo[b]furans.

The palladium-catalyzed coupling in imines, chloroformates, organotin reagents and carbon monoxide has led to the one-pot formation of ketocarbamates. This method has provided an alternate method for imidazolones from five simple building blocks via a one-pot, multicomponent process.

An efficient palladium-catalyzed hydrophenylation of alkynes with sodium tetraphenylborate is described. The procedure yields moderate to excellent amount of phenyl alkenes under mild conditions.

A simple and efficient method to prepare benzyl [alpha],[beta],[beta]-trifluoroacrylate by [Et.sub.2]AlCl-catalyzed reductive Br-F elimination of benzyl 2-bromo-2,3,3,3-tetrafluoropropanoate is described. The synthesis can also be carried out by the palladium-catalyzed cross-coupling reaction of 1,2,2-trifluorovinylstannane with benzyl chloroformate.

The palladium(II)- or silver(I)-catalyzed reactions of [alpha]-amino (2-alkynylphenyl)methylphosphonate which provides a novel and efficient route to 2,3-disubstituted-2H-isoindol-1-ylphosphonate or 2,3-disubstituted-1,2-dihydroisoquinolin-1-ylphosphonate is described.

A series of Pd(0)-catalyzed hydrostannation of E- and Z-enynols variously substituted is examined in order to determine how the nature of the substituents on the alkene bond affects the regiochemical course of these reactions. It is shown that [alpha]-vinyl stannanes are obtained from Z-enynols having different substituents on the double bond regardless of their electronic, steric or chelating natures.

The asymmetric hydrogenation of the activated imines in trifluoroethanol, which can be very effectively catalyzed by various palladium (Pd) or bisphosphines complexes is explained. These imines are found to give numerous useful chiral sultam derivatives on hydrogenation, which can be further used as important synthetic intermediates and structural units of agricultural and pharmaceutical agents.

The synthesis and formation of the dimethyl gloiosiphone A, spiro[4,4]nonane skeleton is described by using the palladium-catalyzed domino cyclization of a linear 7-methylene-2,10-undecadienyl acetate. The one-pot two-step allylation is found to be a result of the oxidation of allylic ether moiety, in addition to the transformation of the vinyl group to an exo-methylene unit, giving the desired product.

3-Methylene-2,3-dihydro-1H-quinolin-4-ones are prepared by the palladium-catalyzed cyclocarbonylation reaction of o-iodoanilines with allenes and CO in 1-butyl-3-methylimidazolium hexafluorophosphate. It is found that the ionic liquid as the solvent and promoter enhances the efficiency of the cyclocarbonylation while at the same time the recylclability of the system of ionic liquid or catalyst is also illustrated.

The regioselective palladium-catalyzed formate reduction of allylic acetates in five- to eight-membered heterocycles to transform the endo-olefin to the exo-position is described. The palladium-catalyzed formate reductions of allylic substrates are an effective method to isomerize the endocyclic olefin formed by ring-closing metathesis (RCM) to the exo-position.

The regioselective palladium-catalyzed formate reduction of allylic acetates in five- to eight-membered heterocycles to transform the endo-olefin to the exo-position is described. The palladium-catalyzed formate reductions of allylic substrates are an effective method to isomerize the endocyclic olefin formed by ring-closing metathesis (RCM) to the exo-position.

The proper choice of ionic liquid (IL) and the base has enabled the Pd-catalyzed Heck arylation of allyl alcohols in tetraalkylammonium ILs to be highly selective toward the formation of either aromatic carbonyl compounds or aromatic conjugated alcohols. The results have also shown that a comparable control on the selectivity can be reached with allyl alcohols, avoiding the necessity for aryl triflates or toxic and costly inorganic additives.

Vinylphosphine-borane complexes are synthesized by palladium-catalyzed C-P cross-coupling of vinyl triflates with secondary phosphine-boranes. The versatility of this method is proved by using many triflates and diaryl-, dialkyl- and alkylarylphosphine-borane precursors and chiral enantiopure phosphine-boranes are synthesized from chiral triflates.

An alternative methodology to [S.sub.N]Ar methodology is described for the synthesis of 4-aminoquinolines. Palladium catalysis is used as a key step for forming the desired C-N bond under conditions that are milder and more convenient than the existing [S.sub.N]Ar methodology.

The reaction of diallyl malonates with an aryl group (aryl - Ph or 2- or 4-N[O.sub.2][C.sub.6][H.sub.4]) at the [alpha]-position, which underwent efficient Pd-catalyzed decarboxylative allylation at room temperature, is reported. The reaction afforded excellent yields of esters with a benzylic quaternary carbon center at the [alpha]-position, which could be transformed into many biologically active compounds.

A phosphine-free palladium-catalyzed method is described for direct C-arylation of free (N-H)-indoles and pyrroles with iodo- and bromoarene donors. This procedure has provided a rapid entry to a wide range of C-arylated (N-H)-indoles including derivatives of tryptamine.

A new functionalization of indoles through the Pd[(OAc).sub.2]-catalyzed reaction of indoles with 2-acetoxymethyl-substituted electron-deficient alkenes to afford 3-(2-methoxycarbonyl-2-propenyl)indoles in which [beta]-OAc functional group was used for the regeneration of Pd(II) species is reported. It was found that for N-protected indoles the reaction proceeded smoothly in the presence of 5 mol % of Pd[(acac).sub.2] and 10 mol % of PP[h.sub.3] at 80 degree Celsius in HOAc, while for N-unprotected indoles, the reaction was carried out by using 5 mol % of Pd[(dba).sub.2] or 2.5 mol % of P[d.sub.2][(dba).sub.3]-CHC[l.sub.3] with 10 mol % of 2,2'-bipyridine as the catalyst in toluene.

Palladium-catalyzed allylic alkylation of sulfenate anions, generated from beta-sulfinylesters by retro-Michael reaction takes place under biphasic conditions. This new reaction provides a simple, smooth and efficient route to allyl sulfoxides in good yields.

The study of palladium-catalyzed tetrahydropyran synthesis was started as a stereospecific 1,3-chirality transfer could be expected in either syn-SN2' or anti-SN2' process intromolecularly. Full accounts of the stereochemical results in the palladium-catalyzed cyclization reactions of zeta-hydroxyallylic alcohols and a new stereospecific synthetic method for 2,6-disubstituted tetrahydropyrans is reported.

A general and high-yielding methodology is developed for the Suzuki reaction in aqueous phase in a short reaction time under mild conditions. This method is useful and attractive for the synthesis of biaryls due to its high efficiency and use of only cosolvent without other additives and ligands.

The asymmetric construction of alpha-alkylidene-gamma-butyrolactams from palladium(II)-catalyzed intramolecular enyne cyclization of N-allylic 2-alkynamides is described. Pd(OAc)2 combined with nitrogen-containing ligands catalyzed the cyclization of (Z)-N-allylic 2-alkynamides in acetic acid to afford the alpha(Z)-acetoxyalkylidene-gamma-butyrolactams in high yield and high stereoselectivity.

A new synthetic route leading to a PdH precatalyst in one step from a stable NHC salt and the commercially available Pd(acac)2 is described. The resulting complex, (IPr)-Pd(acac)Cl has shown excellent catalytic activity in the Buchwald Hartwig and the alpha-ketone arylation reactions using aryl chlorides under milk reaction conditions.

Results on the Suzuki coupling reaction of 2-haloselenophenes with boronic acids catalyzed by palladium salt are presented and a new route established to prepare 2-arylselenophenes and 2,5-diarylselenophenes in good yields is described. In addition, by this protocol unsymmetrical aryl ketones were also obtained from 2-iodoselenophene and boronic acids through a carbonylative process.

Cross-coupling reactions of biphenyl compounds that were investigated and still-growing number of efficient catalysts with various ligands that were available for the transformations is discussed. It was seen that the Stille coupling was superior to the other methods and enabled the synthesis of the title compounds with diverse connectivity.

A straightforward method for the preparation of both (Z) and (E)-alpha-fluorostilbenes was developed. The results revealed that the route to both (Z)- and (E)-alpha-fluorostilbenes was highly stereoselective, highly efficient and was suitable for scale-up preparation compared to existing methods.

The syntheses and characterization of two tetrathiafulvalene (TTF) derivatives bearing pyridine-based substituents and 1,5'-dimethyl-6-oxoverdazyl radicals are described. Although several organic donor radicals, which carry a stable radical unit, are reported, this is the first for which the PI-donor is TTF and the pi-radical is verdazyl.

A significantly improved procedure that provides efficient access to a highly congested 1,8-diacridylnaphthalene fluorosensor is reported. Screening of palladium-catalyzed Negishi, Kumada, Suzuki, Hiyama, and Stille coupling methods showed that the latter affords highly congested 1,8-diarylnapthalenes in superior yields.

cis-Oligo(phenylenevinylene)s (OPVs) are synthesized by Suzuki-Miyaura coupling of arylboronic acids with (Z)-bromoalkenes in over 96% geometrical purity. Effect of PI-conjugation chain length on photoisomerization behavior of OPVs is described.

The catalytic behavior of three commercially available PdEnCat catalysts was explored. Kinetic data coupled with transmission electron microscopy and solvent-dependent investigation were used to support the results.

The direct coupling of aryl halides to prepare symmetrical and unsymmetrical biaryls was performed successfully in poly(ethylene glycol) (PEG) using Pd(OAc)2 as the catalyst in the absence of other additives or reductants. Excessive PEGs induce the increase of hydrodehalogenation product, and the best selectivity to biaryl is obtained when the concentration of the hydroxyl group in PEG achieves 100 mol % relative to aryl halides.

An efficient new route for the synthesis of benzimidazo-[1,2-alha]quinolines is developed through the palladium-catalyzed intramolecular Buchwald-Harwtig aryl amination of newly synthesized 2-(2'-bromoanilino)quinolines. Substituted benzimidazoles and their azino fused variants have attracted considerable attention from medicinal and synthetic organic chemists because of the wide range of biological activities displayed by this class of compounds.

A comparative study of the palladium-catalyzed arylation and heteroarylation of 5-bromoazolopyrimidines shows that aryl and electron-rich heteroaryl boronic acids gave higher yields than those obtained using the corresponding aryl and heteroaryl tributyl stannes. In contrast, the reaction with electron-poor heteroaryl tributyl stannanes gave better results than the corresponding boronic acids.

The trans-bis[2-(2-chloroethyl)pyridine]palladium chloride was prepared and structurally characterized by X-ray spectroscopy and computational study. The reaction of the palladium complex with quinuclidine in CH(sub 3)CN, at 25 degree Celsius, leads to competing elimination and displacement reactions with formation of vinylpyridine and chloroethylpyridine in the ratio of 1.5:1.

Functionalized enol tosylates to be robust substrates undergo Suzuki-Miyaura, Sonogashira and Stille cross-coupling reactions to give stereodefined trisubstituted unsaturated esters. A rare example of a Suzuki coupling reaction of an enol tosylate with methylboronic acid and potassium trifluoroorganoborates is discussed.

The palladium hydroxide on carbon efficiently catalyzes intra and intermolecular direct arylation reaction of aryl iodides and bromides, providing excellent arylation-to-hydrodehalogentation ratios with broad scope for both intra- and intermolecular arylation processes. Studies aimed at determining the nature of active catalyst indicate that an active homogenous palladium species is produced under the reaction conditions.

The heterocyclic ring formation by means of PdI2-catalyzed oxidative cyclization-alkoxycarbonylation reactions to aliphatic acetylenic ketones is investigated. It is found that cyclopentenone, dihydropyridinone and tetrahydropyridinedione derivatives, formed when the reaction is carried out at higher temperature and for a long time, can also be selectively obtained through an acid treatment of tetrahydrofuran and oxazoline derivatives.

A new method for the synthesis of thiocarbamates is developed. When dialkyl or diaryl disulfides are allowed to react with secondary amines and carbon monoxide in the presence of a catalytic amount of a palladium complex, the thiocarbamates are obtained in moderate to good yields.

Proazaphosphatrane ligands in combination with Pd2(dba)3 generate highly active catalysts for Buchwald-Hartwig amination of aryl chlorides. Either a 1:1 or 2:1 ratio of ligand to Pd was found to be effective.

Highly enantioselective palladium-catalyzed asymmetric allylic alkylation using a novel chiral pyrrolidinyl-containing amino-phosphine ligands having a hydroxyl group is described. The trialkylsilylated aminophosphine ligand gave good results in the palladium-catalyzed asymmetric allylic alkylation.

A new method is developed for the synthesis of 2-substituted tetrahydroquinolines via the Pd(0)-catalyzed intramolecular hydroamination of anilino-alkynes. This method is implemented for the synthesis of alkaloids such as (_)-angustureine and (_)-galipinine and also for natural products containing tetrahydroquinoline moiety.

A palladium-catalyzed annulation reaction by aryne and 1-(2-bromophenyl)-1H-indoles as an efficient method to synthesize indolo[1,2-f]phenanthridine under mild conditions with good yields is demonstrated.

An efficient method to obtain geometrically pure (E)-alkenes from (Z)-alkenes through reaction of aryl- or alkyl-substituted (Z)-alkenes with tributyltin hydride and triethylamine by using a palladium acetate as catalyst is demonstrated.

The synthesis of 2-substituted indenes is achieved through a palladium-catalyzed carboannulation of propargylic carbonates with nucleophiles. This new method has accommodated a variety of nucleophiles and has afforded the substituted indenes in good yields.

Palladium-catalyzed arylation of alpha,beta-unsaturated gamma-lactam is carried out to make the core structure of Erythrina alkaloids. The intermediates could be prepared readily by condensation of the corresponding amine and cyclic keto-ester.

An efficient Pd(OAc)(sub 2)/Dabco-catalyzed Stille cross-coupling reaction procedure is developed. In the presence of Pd(OAc)(sub 2) and Dabco (triethylenediamine), various aryl halides including aryl iodides, aryl bromides, and activated aryl chlorides are coupled efficiently with organotin compounds to afford the corresponding biaryls, alkene, and alkynes in good to excellent yields.

Palladium-catalyzed dehydroarylation of triarylmethanols by using the bulky ligand P(1-Nap)(sub 3) is demonstrated. Hydroarylation of some unsaturated compounds with alcohol has also been shown.

Pd-catalyzed cross-couplings of the trichlorophenyl-, dichlorodiphenyl-, and chlorotriphenylgermanes with aryl bromides and iodides in the presence of tetrabutylammonium fluoride in toluene with addition of the measured amount of water is described. [Super 19]F NMR studies suggested that formation of the fluorophenylgermanes and the hypervalent germanate species as possible intermediates in the reaction with no haloligand required to be present on the Sn center, as tetraphenyltin efficiently transferred up to four phenyl groups during fluoride-promoted couplings with aryl halides.